Conventional golf balls can be divided into two general constructions: solid and wound. Solid golf balls include one-piece, two-piece (i.e., solid core and a cover), and multi-layer (i.e., solid core of one or more layers and/or a cover of one or more layers) golf balls. Wound golf balls typically include a solid, hollow, or fluid-filled center, surrounded by a tensioned elastomeric material, and one or more cover layers. Solid balls have traditionally been considered longer and more durable than wound balls, but some solid constructions allegedly lack the “feel” provided by the wound construction—this deficiency is typically noticed by more advanced players.
By altering ball construction and composition, manufacturers have been able to vary a wide range of playing characteristics, such as compression, velocity, “feel,” and spin, optimizing each or all for various playing abilities. In particular, a variety of core constructions, such as multi-layer balls having multiple cover layers and/or core layers, have been investigated and now allow many solid golf balls to exhibit characteristics previously achieved solely with a wound construction. These solid layers are typically formed from a number of thermoset or thermoplastic polymeric compositions and blends, including polybutadiene rubbers, polyurethanes, ethylene-based ionomers, and polyureas.
There is a need, however, for a means of altering the physical and mechanical properties of conventional golf ball layer materials, such as those discussed above. Commonly, manufacturers will attempt to improve one material property which, unfortunately, has a deleterious effect on one or more different material properties. Therefore, compositions in which unconventional properties may be imparted on a particular material or in which material properties may be altered without adversely affecting other desirable properties, are of importance. The present invention describes such compositions and there use in a variety of golf ball core and cover layers.